The main objective is to determine how the speech of deaf children differs from that of hearing children. The acoustic, articulatory and perceptual characteristics of both deaf and normal speech will be examined for systematic differences. Both segmental and suprasegmental errors in the speech of deaf children will be determined and their mutual effect on intelligibility evaluated. Acoustic analyses will be carried out on both deaf and normal speech to determine which acoustic parameters are most directly affected by these errors. The acoustic analysis will be mainly by digital computer using digital techniques for determining power spectrum, formant frequencies and bandwidths, fundamental frequency and short-term energy. The relation between residual hearing and speech production will be examined to determine how speech intelligibility and frequency and type of articulatory errors are related to residual hearing for speech. Residual hearing will be measured by standard audiological techniques as well as by specially constructed speech reception tests designed to measure reception of those features most subject to error in the child's own speech production. BIBLIOGRAPHIC REFERENCE: Acoustical Articulatory and Perceptual Characteristics of the Speech of Deaf Children, H. Levitt, C. R. Smith, and H. Stromberg in Speech Communication; Proc. of the Speech Communication Seminar, Stockholm. G. Fant (Ed.) pages 129-139. John Wiley and Sons, 1976.